S-PM mat is used as basic material for anti-corrosion wrapping on steel pipelines that buried underground for oil or gas transportation. It has good compatibility with coal tar, pitch etc, so the underground transportation pipe wrapped with coal tar and pitch S-PM mat possesses excellent resistance to permeate and various mediums and has longer service life and less repairing and changing cost. Therefore, S-PM series is the ideal basic material of internal and external wrapping strip.